There is the poem by Thomas Tusser that reads:
Sweet April showers
Do spring May flowers
And a song that is called 'March Winds and April Showers' that goes:
March winds and April showers
Make way for sweet May flowers
And then comes June, the moon and you
March winds and April showers
Romance will soon be ours
An outdoor paradise for two
With your lips to mine in a thrill divine
I'll be so inspired
That I'll get you the Moon for a toy balloon
March winds and April showers
Make way for happy hours
And May time, June time, love time and you
There is also a poem by Karen Chappell called 'April Showers':
April showers bring May flowers,
That is what they say.
But if all the showers turned to flowers,
We’d have quite a colourful day!
There’d be bluebells and cockleshells,
Tulips red and green,
Daffodils and Chinese squill,
The brightest you’ve ever seen.
You’d see tiger lilies and water lilies,
Carnations pink and blue,
Forget-me-not and small sundrop
Glistening with the dew.
We’d have fireweed and milkweed
And many more different flowers.
Mexican star and shooting star,
Falling in the showers.
And if all the showers turned to flowers
On that rainy April day,
Would all the flowers turn to showers
In the sunny month of May?
And Sara Coleridge wrote this one:
'A Calendar'
January brings the snow;
Makes our feet and fingers glow.
February brings the rain,
Thaws the frozen lake again.
March brings breezes, loud and shrill,
To stir the dancing daffodil.
April brings the primrose sweet,
Scatters daisies at our feet.
May brings flocks of pretty lambs
Skipping by their fleecy dams.
June brings tulips, lilies, roses,
Fills the children's hands with posies.
Hot July brings cooling showers,
Apricots and gillyflowers.
August brings the sheaves of corn,
Then the harvest home is borne.
Warm September brings the fruit;
Sportsmen then begin to shoot.
Fresh October brings the pheasant,
Then to gather nuts is pleasant.
Dull November brings the blast;
Then the leaves are whirling fast.
Chill December brings the sleet,
Blazing fire and Christmas treat.
More along these lines are:
'Through the Year'
(by Flora Willis Watson)
January falls the snow,
February cold winds blow,
In March peep out the early flowers,
And April comes with sunny showers.
In May the roses bloom so gay,
In June the farmer mows his hay,
In July brightly shines the sun,
In August harvest is begun.
September turns the green leaves brown,
October winds then shake them down,
November fills with bleak and smear,
December comes and ends the year.
And this one by one of my favourite poets:
The Months
(Christina Rossetti)
January cold and desolate;
February dripping wet;
March wind ranges;
April changes;
Birds sing in tune
to flowers of May,
And sunny June
Brings longest day;
In scorched July
the storm-clouds fly,
Lightning-torn;
August bears corn,
September fruit;
In rough October
Earth must disrobe her;
Stars fall and shoot
In keen November;
And night is long
And cold is strong
In bleak December.
And the fantastic show 'Pennies From Heaven' (which featured the song 'March Winds and April Showers') has this poem as narrated by Freddy Jones and thus presumably created by Dennis Potter:
January, snowing.
February, rain.
March, with winds a-blowing.
April, sun again.
May, a world of flowers.
June, with dancing leaves.
July, long lazy hours.
August, golden sheaves.
September, apples redden.
October, winter's near.
November, skies all leaden.
December, Christmas cheer.
Those are all I can kind. Sorry if I haven't been of much help.